The replacement of the standard water heater with a new one has been described by theoretical
analysis of laws and regulations in which is described a correct way for calculations of thermal
energy, needed for family house heating, and also gas technology and their working principles.
Calculations and comparisons for the current and the future conditions have been conducted by
Thorium A+ software, to get the insight of thermal energy consumption and savings in the
future. As a new condition, a new gas condensing boiler was considered with installation of
thermoregulatory valves on the radiators. Savings in primary energy consumption and costeffectiveness
of the investment with the incorporation of new technologies have been proven